Drive release for taper threading die head



July 10, 1956 c. H. INGWER 2,753,575

DRIVE RELEASE FOR TAPER THREADING DIE HEAD Filed Dec. 2, 1953 2 Sheets-Sheet 1 INVENTOR. CARL lNl VE/P BY a.

HAS ATTORNEY y 1956 c. H. INGWER 2,753,575

DRIVE RELEASE FOR TAPE-R THREADING DIE"HEAD Filed Dec. 2, 1953 2 Sheets-Sheet 2 I IN" n 2 I I l I 1 I 65 6/ 1., 63 HH 1 h I I mg um WNW INVENTOR. an. H. uvs Wife United States Patent DRIVE RELEASE FOR TAPER THREADING DIE HEAD Carl H. Ingwer, Elyria, Ohio, assignor to The Ridge Tool Company, Elyria, Ohio Application December 2, 1953, Serial No. 395,663 Claims. (Cl. Iii-420.5)

This invention relates to improvements in threading tools and more particularly to a tool wherein the threading operation is accomplished by means of a threaded barrel in engagement with a chaser frame which is adapted to be moved over the disposed pipe thereby carrying the chasers into engagement with the pipe cutting threads thereon.

This invention has been incorporated into several different types of threading tools such as illustrated in Ingwer et al., 2,584,463, issued February 5, 1952, and application, Serial No. 155,178, Ingwer et al., filed April 11, 1950, now Patent No. 2,680,861, dated July 15, 1954, to show its adaptability to tools of this classification.

In the usual type of threading device in practice today, the number of threads that are out upon a pipe is left to the discretion of the operator of such tool, and as is most often the case the operator allows the tool to operate for too long a duration. The result is that the threaded barrel or chaser frame is given too great a longitudinal movement forcing one of the above elements into engagement with associated parts of the tool causing the unit to bind and lock, the reaction being substantially the same when a bolt is threaded into a hole and therein tightened with a wrench. Before the tool can be used again, it is necessary to dismantle it, separating the binding parts.

The present invention, by means of its novel construction has removed the possibility of an occurrence of such a time consuming and costly error and such preventive qualities have been so added without any material increase in the cost of producing the threading tool.

Other advantages of the invention will become more apparent by reference to the description herein and which is illustrated by the accompanying drawings which form a part of this specification.

In the drawings:

Fig. 1 is an elevational sectional view of the device showing the embodiment of the invention; and

Fig. 2 is an elevational view of similar type of threading tool showing the embodiment of the invention therein.

Referring now to the drawings throughout which like parts are designated by like reference characters, the device includes a work holder 2, Fig. l, which is adapted to secure the pipe to the device. The holder is connected by legs 3 to a ring gear 4- having teeth 5 which are arranged for driving engagement with a pinion 9 as hereinafter more fully described.

The ring gear 4 is provided with a reduced cylindrical barrel 6, the outer surface of which provides a bearing surface for the housing 7.

The housing 7 comprises a generally cylindrical outer portion 10 adapted to extend over and protect the ring gear 4, and an inwardly extending flange 8, the inner periphery of which is adapted to be seated on barrel 6 which provides a bearing support therefor. The barrel 6 is sufficiently long to extend beyond the flange to allow a rectangular groove to be placed about the periphery and into which is seated a split ring 11. The ring engages the outer surface of the flange 8 to hold the housing in its assembled position relative to the ring gear as the housing rotates on the barrel.

A hollow boss 21 is formed on the housing as seen in Fig. 1 and is adapted to house and support the drive pinion 9 and its bearing 23. The drive pinion is provided with teeth 24 adapted to mesh with the teeth 5 on the ring gear, and is carried by a round shaft 25 which can be provided with a square, hexagonal, or triangular driving end 36 to which may be attached a means for producing the rotative power necessary to the operation of the device.

The shaft may be provided with an end section 26 having a smaller diameter than the remaining portion and journalled in an opening provided in the housing 7.

The shaft is rotatably journalled in an oilless sleeve bearing 23 which is threaded at 28 and adapted to be screwed into a threaded opening of the housing 7. The interior of the sleeve is provided with graphite rings 29 which are seated in grooves 29' and adapted to be the lubricating media for the drive shaft. A flange 30 adjacent the threaded end of the sleeve prevents the bearings from extending too far into the housing and provides a rigid support for the sleeve when tightened into place.

A plurality of chaser posts 31 are journalled to the housing being equally spaced radially about the flange 8. One end 32 of each chaser post is adapted to be in a press fit relationship with an opening 33 in the housing being secured therein by a headless pin 34.

The inner face of each chaser post is cut away at 35 to provide an inclined flat plane surface upon which the base end of a chaser engages and slides over when the tool is operated.

The chaser holder 37 includes a frame 38 having bosses 39 equally spaced radially about the periphery of the frame, and channels 40 extending radially through each boss adapted to house the chasers 41. A hollow boss 42 is adapted to receive the end of the sleeve bearing 23 adjacent the driving end of the shaft and thereat provide a rigid support for the bearing and disposed shaft. Holes 47 adapted to act as a guide means for the chaser posts 31 are seen to extend through the top portion of each of the radial bosses through which the posts slide freely when the tool is in use. The radial channels 40 extend outward and open into the holes 47 thereby providing a means by which the chasers can slidably engage the chaser posts. The inner face of the frame 38 is provided with a circular recess in which the flange 45 of an exteriorly threaded sleeve 43 is secured to the frame by screws 44 that extend through the flange 45 and are in threaded engagement with the frame.

The flange 45 covers the channels 40 thereby providing a closed guide means for the chasers. The threads 48 on the outer periphery of the sleeve are in threaded engagement with the threads on the barrel 6. The inner face of the flange 45 is provided with blind holes 49 in which bullet catches are disposed having spring pressed balls 50 adapted to engage in detents in the side of the chasers.

A groove 4-6 generally rectangular in cross section is formed about the outer periphery of the sleeve 43 adjacent the flange 45, and prevents the flange from being pressed into rigid engagement with the housing 7, since the width of the groove is greater than the width of the threaded part 6 on the barrel which is sufficient to allow an adequate number of threads to be formed on a work. piece and yet prevent the device from looking and thereby becoming inoperative.

Included within the concepts of this invention is the embodiment shown in Fig. 2 as having the same inventive features as the original embodiment.

--The distinction between the two deviceslies in the size of pipe that each is capable of handling but it is to be understood that the invention is adaptable to all such similar devices, the drawings being illustrative of only two which is thought to be adequate for this specification.

The embodiment of Fig. 2 comprises a workholder 60 which is generally circular in shape and adapted to receive and rigidly secure therein a section of pipe. A flange 61 extends outward from the upper edge of the work holder and bosses 62 are struck downward from the lower peripheral edge of the flange. Centering lugs 63, only one being shown, are adapted to be received in holes formed in the bosses and extend through the work holder. The centering lugs are adapted to be radially adjusted by means of a ring guage 64 which positions the lugs so that the pipe is centrally positioned whereby the threads on the pipe will be of even depth about the periphery thereof. A lock bolt 65 in threaded engagemerit with the work holder is adapted to secure the pipe in the device.

The work holder is connected by legs 66 to an interiorly threaded barrel 67 which is in threaded engagement with an exteriorly threaded sleeve 68. The sleeve has a circular flange projecting radially outward from the lower edge thereof which is adapted to seat in a recess formed in the chaser frame 70 and therein rigidly secured enabling the chaser frame and sleeve to be movable as one unit. The upper portion of the outer peripheral surface of the sleeve is threaded and engageable with the barrel of the work holder. A peripheral groove 72 rectangular in cross section is formed on the lower portion of the outer surface of the sleeve and extends downward to the flange. The chaser frame 70 is generally circular in form with an interiorly threaded boss 73 extending outward from the outer periphery of the frame which is adapted to receive a handle to provide a means to operate the tool.

Channels 74 spaced radially within the chaser frame are adapted to receive chasers 75. A cam plate 76 is placed over the flange and has cam members 77 extending downward through openings in the flange. Each chaser 75 has cam surfaces 78 that are engageable with the cam members 77, and upon rotation of the cam plate the cam members force the chasers radially toward the axis of the tool to position said chasers into proper thread cutting engagement with the end of the pipe.

Chaser posts 79 extending vertically upward from the cam plate are in slidable engagement with openings 80 locatedwithin a change plate 81 which is seated in a groove on the barrel 67 and thereat secured by a-split ring 82. edge of the change plate and are in sliding engagement with upright guides 85 formed on a drive plate 86 so that relative angular movement between the change plate and drive plate is prevented.

A thumb lever 87 is adapted to secure the chasers in their relative position subsequent to the setting of the chasers for thread cutting.

In operation the embodiment of Fig. 1 is placed over the end portion of the pipe to be threaded and the chasers 41 are advanced until they engage the outer surface of thepipe. The pinion shaft 25 is then rotated clockwise by means of a wrench or a power drive. The pinion 9 is thereby rotated clockwise and travels around the ring gear 4 carrying with it the housing 7 which rotates on the barrel 6. The housing through the posts 31 and the sleeve 43 rotates the chaser holder 37. The sleeve 43 through its threaded engagement with the barrel 6 travels inward toward the pipe as the shaft is rotated clockwise drawingthe chasers 41 into thread cutting engagement with the pipe, and the power is applied continuously until the desired number of threads are cut. ltis apparent that if the power is applied until the threaded pprt on of the sleeve 43 has passed through the barrel ,6, the inward Grooves 83 are formed on the outer peripheral travel of the chasers 41 would be stopped upon the barrel 6 completely entering the peripheral groove 46. The chaser holder 37 would then rotate freely on the barrel until the power is reversed and the chaser frame 38 is drawn out. As can be seen from the drawings, the taper of the chaser engaging faces of the posts is such that the chasers are now withdrawn from cutting engagement with the surface of the pipe.

The embodiment of Fig. 2 is similar in. operation in that the pipe is inserted and secured in the workholder 6i and the chaser frame 7'0 is advanced until the chasers 75 engage the end of the pipe. A handle is screwed into the boss 73 providing power means to rotate the chaser frame. When the frame 79 is rotated clockwise, the sleeve 68 through its threaded engagement with the barrel 67 travels inward over the pipe drawing the chaser '75 into thread cutting engagement with the pipe. It is realized that in this embodiment, the chaser frame will advance into the barrel only as long as there is threaded relationship between the barrel and sleeve. When the threaded portion of the sleeve has completely passed through the barrel and the barrel enters into the peripheral groove 72, the chaser frame ceases its rectilinear movement and rotates freely on the barrel.

it is therefore apparent that by my invention, 1 provide a means whereby the elements comprising the thread cutting tool are prevented from jamming or binding and thereby causing the tool to become inoperative.

Having thus described my invention, I am aware that numerous changes may be made therefor without departing from the spirit or scope of my invention.

I claim:

1. A thread cutting tool having a work holding member and a chaser carrying member, a barrel member on said work holding member having a threaded portion in threaded engagement with a sleeve member on said chaser carrying member, said chaser carrying member being rotated by drive means in driving relationship with said work holding member whereby said sleeve member is advanced into said barrel member providing rectilinear movement for said chaser carrying member toward said work holding member, said work holding member carrying posts disposed in controlling engagement with said chasers, said posts comprising means to retract the chasers out of engagement with the work as the sleeve member is advanced into the barrel member by said threaded engagement, groove means formed on said sleeve member, arranged to completely receive said threaded portion on said barrel means and operable to stop said sleeve member from advancing completely into said barrel member andthereby prevent said work holding member from clashing and thereafter binding with said chaser carrying member to make said cutting tool inoperative.

2. In a thread cutting tool having a work holding member and a chaser carrying member, a barrel member on said work holding member having a threaded portion in threaded engagement with a sleeve member on said chaser carrying member, said chaser carrying member being rotated by drive means in driving relationship with said work holding member whereby said sleeve member is advanced into said barrel member providing rectilinear movement forsaid chaser carrying member toward said work holding member, said work holding member having chaser controlling posts in engagement with said chasers and means formed thereon to retract the chasers out of engagement with the work as the chaser carrying member is moved toward the barrel member bysaid threaded engagement, peripheral groove means formed on said sleeve member arranged to completely receive said threaded portion on said barrel member, and operable to stop said sleeve member from advancing completely into said barrel member and thereby preventing said work holding member from clashing and thereafter binding 3. A thread cutting tool having a work holding member, and a chaser carrying member, drive means in driving relationship with said work holding member to provide rotational movement for said chaser carrying member, means on said work holding member in threaded engagement with said chaser carrying member and driven by said drive means to effectuate rectilinear movement of said chaser carrying member, said work holding member having posts provided with chaser engaging surfaces in engagement with said chasers and said chasers being movable outwardly under control of said posts and out of engagement with the work as the chaser carrying member is moved toward the work holding member by said engaging means, and means on said chaser carrying member arranged to completely receive said engaging means on said work holder and operable at the end of a thread cutting cycle to stop the rectilinear movement of said chaser carrying member when said work holding member and said chaser carrying member are in a predetermined spaced relationship to prevent clashing and subsequent binding of said members.

4. A thread cutting tool having a work holding member and a chaser carrying member, drive means in driving relationship with said work holding member to provide rotational movement for said chaser carrying member, means on said work holding member in threaded engagement with said chaser carrying member and driven by said drive means to effectuate rectilinear movement of said chaser carrying member, said work holding member having posts provided with chaser engaging surfaces in engagement with said chasers and said chasers being movable outwardly under control of said posts and out of engagement with the work as the chaser carrying member is moved toward the work holding member by said engaging means, groove means formed on said chaser carrying member arranged to completely receive said engaging means on said work holder and being operable to disengage said engaging means on said work holding member from said chaser carrying member when said members are in a predetermined spaced relationship to stop the rectilinear movement of said chaser carrying member at the end of a thread cutting cycle thereby preventing clashing and subsequent binding of said members.

5. A thread cutting tool having a work holding member and a chaser carrying member, drive means in driving relationship with said work holding member to provide rotational movement for said chaser carrying member, a threaded portion on said work holding member in engagement with said chaser carrying member and driven by said drive means to effectuate rectilinear movement of said chaser carrying member, said work holding member having posts provided with chaser engaging surfaces in engagement with said chaser and said chasers being movable outwardly under control of said posts and out of engagement with the work as the chaser carrying member is moved toward the work holding member by said engaging means, groove means formed on said chaser carrying member having a width greater than the axial length of said threaded portion of said work holding member and being operable at the end of a thread cutting cycle when said members are in a predetermined spaced relationship to completely receive said threaded portion and stop the rectilinear movement of said chaser carrying member thereby preventing clashing and subsequent binding of said members.

References Cited in the file of this patent UNITED STATES PATENTS 

